The prevalence of bacterial vaginosis and other lower genital tract infections were determined in women from a developing community. Patients were recruited from four out-patient clinics of a large urban tertiary referral hospital serving the indigent Black population of KwaZulu/Natal, South Africa. A total of 208 women attending the sexually transmitted diseases (STD) (n = 51), colposcopy (n =50), family planning (n = 52) and antenatal (n = 55) clinics were investigated. Endocervical and vaginal specimens were collected for microbiological investigation of recognised sexually transmitted pathogens. Estimation of vaginal pH, amine test and wet smear microscopy were performed at the bedside. Peripheral venous blood was obtained for serological tests for syphilis, hepatitis B surface antigen and antibody to the human immunodeficiency virus (HIV). Vaginal infections were detected in a total of 50% (104) of women, endocervical infections alone in 9% (18) and concurrent vagino-endocervical infections in 20% (41). Bacterial vaginosis (BV) was diagnosed in 35% (73) and its prevalence amongst different clinic populations ranged from 25% to 41% with no significant differences between any groups. Trichomoniasis was detected significantly more often in women attending the STD and antenatal clinics. Endocervical infections were found mainly in women attending the STD clinic, though the prevalence of Chlamydia trachomatis amongst the other clinic attenders ranged from 13% to 20%. Micro-organisms such as Gardnerella vaginalis, Mycoplasma hominis, anaerobes and curved Gram-negative rods were found in significantly higher number of women with BV. This study confirms the high prevalence of vaginal, endocervical and mixed vagino-endocervical infections in women from developing communities. The high prevalence of bacterial vaginosis as a single infection and its association with other recognised sexually transmitted pathogens in a large proportion of women, is of significance since such infections not only predispose to ascending upper genital tract infections but are also associated with complications in pregnancy such as premature rupture of membranes, preterm labour and endometritis.